Cleansing fabrics.



To alt whom it may concern:

or ltXHLtF & HBERS,

toss Reference UNITED s rn rns PATENT OFFICE.

HOWARD B. BISHOP, on NEW YORK, N. Y.

CLEANSING FABRICS.

No Drawing.

-rust stains and other stains, and "to sour the fabrics so that the bluing will set properly.

Hitherto oxalic acid has been used to neutralize the traces of alkali remaining after the clothes have been washed in soap or and stiff and weakens their fiber.

another detergent so as to enable the bluing to set, and also to remove iron and other stains, and particularly the yellow edges of collars whlch are largely due to the iron .in the blood given off in perspiration. But

oxalic acid makes the clothes feel harsh This is due to the fact that oxalic acid unites with the lime. which is usually present in the clothes or in the washing tank (especially if chlorid of lime has been used as a bleach) and forms calcium oxalate in the form 0 a .fine white, and insoluble powder. This substance settles into the fiber of they clothes, and, beinginsoluble, is rarely removed by the rinsing process. After repeated washings the cloth becomes filled withthis powder, feels hard and stifi, the fibers are weakened, and the turned edges break.

My improvement consists substantially in treating such fabrics wit fluori ilill the form of any of its water soluble compounds which have an acid reaction. For instance, I may use hydrofluoric acid, hydrofluosilicic acid or any of the water soluble salts, such as the acid salts of the alkalis, for. instance, sodium acid fluorid, potassium-acid fluorid, ammonium acid fluorid, or sodium silico fluorid ammonium silico fiuorid or potassium silico fluorid. On account of its cheapness, the sodium salt of hydrofluoric acid is probably the salt best adapted forpractical use, although the ammonlum salt is more readily soluble. These substances do not form aninjurious precipitate and are easily removed by rinsing. I -In carryin out my improvement in the art of cleansing fabrics, I may employ a Specification of Letters Patent.

mixture of two or more fiuorin compounds of the character described.

In using the substances above referred to, I add about one pound to about every thousand pounds of the laundry water (without soap), this treatment preceding immediately the usual addition of bluing, to the laundry water. -In order to neutralize the alkali in the laundry water without using for this purpose the expensive fluorin compound, I may add acid, such as search Hoom Patented F b. 13, 1912. Application filed December 2, 1909. Serial No. 531,096.

acetic acid, by adding the same to the laundry water previously to or simultaneously with the fluorin compound. Such acid may first be mixed with -the fluorin compound and the mixture then add'ed to the water.

I may also employ m improvement in the art of cleansing fab its by mixtures such as fluorincompound or compounds with a gum to form a paste. 'This paste may be applied directly to the stains and this method of employing my invention is of particular value when it is desired to remove very heavy rust stains.

My improvement in the art of cleansing fabrics results in the neutralization of the alkalis and the removal of rust stains and a large number of other stains in which iron ispresent without injury to the fabrics, which is an entirely unexpected result, since hydrofluoric acid and many other water soluble compounds of fiuorin are commonly believed to have a strong destructive action. i J

I claim:

1. The improvement in the art of cleansing fabrics which consists in brlnging fab-- rics having iron stains thereon into contact with a water soluble compound of fiuorin having an acid reaction, substantially as and for the purpose described.

'2. The improvement in the art of cleansing fabrics which consists in bringing fabri cs having iron stains thereon into contact with a solution of a water soluble compound .of fluorin having an acid reaction, substantially as and for the purpose described.

- 3. The improvement in the art of cleans- I ing fabrics which consists in bringing fabrics having iron stains thereon into contact with a solution of hydrofluoric acid, substantially as and for the purpose'described.

4. The improvement in the art of cleans ing fabrics which consists in immersing the same in water, neutrallzing an alkali 1n said water by an acid and adding to the reaction, substantially as and for the pur- 10 water a water soluble compound of fluorin pose described. having an acid reaction, substantially as "P In testimony whereof I have hereunto set and for the purpose described. I my hand in the presence of two subscrlbing 5. The improvement in the art of removwitnesses.

ing iron stains from fabrics which consists HOWARD B. BISHOP. in moistening and treating the portion of Witnesses: i the fabric having the stain, with a water JOHN A. KEHLENBECK, soluble compound of fluorin having an acid GEORGE V. RASMUSSEN. 

